Popliteal Blocks are used at the Hospital for Special Surgery to help alleviate pain after foot and ankle surgery. Patients who have a popliteal block will have the outside 75% of their foot numbed. Because it does not cover the entire foot, this block is often used in combination with a spinal or epidural for surgical anesthesia.

Once you have arrived in the operating room, the anesthesiologist may ask you to turn onto your stomach. The injection may be placed either in the back of knee or on the side of the leg. Once you are in position, your anesthesiologist will provide some sedation intravenously. This will reduce any pain or anxiety you may be having.

When you have achieved a desired depth of sedation, a long thin needle is inserted and directed toward your nerves. You may feel your foot twitch involuntarily -- that is exactly the desired response from the anesthesiologist. When the appropriate response is elicited, a long-acting, lidocaine-like medicine is injected through the needle.

After surgery, your spinal and sedation will be wearing off. At that point, the outside of your foot will be numb. That numbness may last for 4 to approximately 18 hours.

As with any anesthetic, there are risks and benefits to popliteal blocks. These particulars can be discussed with your anesthesiologist before your surgery.